Iron-Mediated Synthesis of Isoxazoles from Alkynes: Using Iron(III) Nitrate as a Nitration and Cyclization Reagent

Zhenzhen Lai; Zhenxing Li; Yawei Liu; Pengkun Yang; Xiaomin Fang; Wenkai Zhang; Baoying Liu; Haibo Chang; Hao Xu; Yuanqing Xu

doi:10.1021/acs.joc.7b02483

Iron-Mediated Synthesis of Isoxazoles from Alkynes: Using Iron(III) Nitrate as a Nitration and Cyclization Reagent

J Org Chem. 2018 Jan 5;83(1):145-153. doi: 10.1021/acs.joc.7b02483. Epub 2017 Dec 18.

Authors

Zhenzhen Lai¹, Zhenxing Li², Yawei Liu¹, Pengkun Yang¹, Xiaomin Fang¹, Wenkai Zhang¹, Baoying Liu¹, Haibo Chang¹, Hao Xu^{1

2}, Yuanqing Xu¹

Affiliations

¹ College of Chemistry and Chemical Engineering, Henan University , Kaifeng 475004, P. R. China.
² State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing , Beijing 102249, P. R. China.

PMID: 29224341
DOI: 10.1021/acs.joc.7b02483

Abstract

A simple and direct method for the iron(III) nitrate-mediated synthesis of isoxazoles from alkynes has been developed; both self-coupling and cross-coupling products could be successfully prepared from alkynes. Meanwhile, for the cross-coupling and cyclizing of two different alkynes examined, the iron-mediated system shows a good chemoselectivity for the synthesis of corresponding isoxazoles. In our method, cheap and eco-friendly iron(III) nitrate is used as the nitration and cyclization reagent, and KI is used as the additive; they both play a positive role in this transformation. Furthermore, a different mechanism for the formation of isoxazoles from alkynes has been proposed.

Publication types

Research Support, Non-U.S. Gov't